Machine-gun unit



oct. 3o, 192s. 1,689,482

S. G. GREEN MACHINE GUN UNIT Filed Jan. 18,1926 2 sheets-Sheet v1 SamuelE Erean L w//ffw/I Oct. 30, 19228.-

s'. G. GREEN l MACHINE GUN UNIT Filed Jan. is, 192e 2 sheets-sheet 2MfW/;

dummy fil ' is illustrated in the accompanying drawingsl Patented ct.13G, ,1928.

' MAcHrNE-GUN UNIT.'

Y Application fuera yprimary' '11s', 192e serial No1/salici.

(GRANTED UNDER THE Acr er Martens-,1188s, As' AMENDED lira-11.130,Y1928;'37'050.' Gr.VV 75,71)v

The invention described hereinV may 'be manufactured andused by or forthe-*Government for governmental purposeswithout the payment to meotany'royalty thereon.V

This invention relates to amachine gun unit and particularlyit hasreference to seai release mechanism applicable torsynchroniz'ed gunsmounted on'aircratt n In mechanisms of the above typecommonly known astrigger motors, the lamount of power required to trip' the sear isconsiderable even in the standard `.30 caliber 'guns and this isespecially true whenthe release ot the sear is accomplished by a transversely sliding member. Asa consequence,-l the mechanism is unreliablein operation: and Y requires frequent readjustment. l

Iii devising an improved trigger4 motor, particular attention has beendirectedto' producing-amechanism which will'be especially applicable tomachine guns oflarge caliber',V

' for example the .50 caliber gun, now AbeintegjextensivelyA used tosupplant the V"standard 'sized weapon. Y .The principal objects of'thisinvention Vthen are :to provide a more accurate anddependable Searrelease mechanism operable on4 application of only la slight torce orpower and positive in its semifautomatic action; to simplify thearrangement by establishing direct connection with the searf therebyavoid ing linkage with its consequent.lost-'motion` with". Themountingofthe triggerfma'y be otanyl suitable character," a simple form beingshown,l `which o comprises"v a support :in the and backlash; to employnovel means traveling a' minimum distance for .assuring'clearn ance whenthe bolt ot the gun arrives in bat'- tery out of time withthe trigger;and,V to in# crease the accessibility for connection with 'the motor ofthe airplane.A v

To'tliese and other ends my invention con-V sists in the'construction;arrangement .andi

combination ct elements;describedhereinafter and pointed outintheclaimsptorining la part of this specification. 'f

AV practical embodiment of myrinveiition wherein: Y Y Fig. 1 isa moreorless diagrammatic view Vshowing the relation between the ,Qjunv andmotor; l Y f Fig, 2 is a longitudinal sectional view taken through theAsear release mechanism, the sear being shownvin elevated or engaged.position; v v

oi the trigger head during reciprocationrg.

' of 'the bolt and forced;r to

3F ig. f3 isa view in rear elevation'otvthei i. A Y- bolt inbatteryshowing-'the normal position Nif iieE 'i STATES, `paraNifriiforFica.

vY: Fig. 4 is a longituc'linalwv sectional viewV showing thepositionassumedby the triggerv liead-A when depressed to disengage the'sear'; F 5 is ay view in 'end` elevation of Figa-4t;

and sear;

views Ain elevationfand Y v A I4 ig.V 12 is ajperspective of the triggerhead.

n Referring thedrawingfby numerals ot' i reference f Y y 'Ihere is shownat 5 thev receiver of a machine gun. in vwhichreciprocates the bolt G oFigs. Y 6, and@` are detail plan views. f showing variouspositioiis ofthe trigger headA Y the well known manner by theV lever 8( The pinisheld-in cocked position by. a sear 9 slidable vertically ingslotsaA out.in the rear face n pinenfiao'inol'osi-'v tion byjaspring 10.): l h'b'p'f Thetrigger or searrelea'se:mechanism/is mounted inthe coverorltop plate 15 ot the vreceiverdirectly. abovetlie posit-ion assumed iby the sear whenthefboltis inbattery. i It f consist-s ressentiallyoi'-fa`verticallyrecipro-fcable rod'or trigger11 piovidedron Aits lowerY lextremity with. a strikerhead-1 2 which inthe' preferredembodimentofthe invention *is ast'to the rod, being shown integral'ithere! forniof'a cylindricalcasing 13, oneend'otv du cedk .portion Y which extendsthrough the plate,Y The cap niitis vharmed wit'hran aperfture 14a -toreceive the-upper Vportion of ,the

trigger- V 11.V A spring 15 encircling s the Y triggerandfcontinedbetween the-base ofthe casing land/a' collar 16'011' the triggerA jnor-Vmaplly'maintains` the 'trigger in the raised p"oV 'sition7 l'the collarbyA engaging the' cap 'nutY serving to limit theaction ofthe springwhile l apin 17 in the trigger exterior ofthe cap limitsthedownwardstroke of the`r trigger i when the sa'ineis'v actuated bj 'thecam `en n e Y a n carryingithe firing piii which is cocked in'i;

V."ll

Vthe shaft l9fconnected to the motorf `The spring l is `furtheranchoredvtoV the casing` -and trigger to limpart rotational movementv tothe trigger and Vrestore the strikerhead 12 to operative or armedposition when the saine has been displaced,V as will presently ,bedescribed. It desired, the striker head Y'can'be rotatably carriedby thetrigger rodand have independent means for restoring it.'Y

The casing 13.` is provided Aat itsV lower lextremity with an extendinglinger 20, which,

asshown in fFig. 3, Yis positioned at'one `side ot: the path ot travelof`the sear 9 and V4en-y gages the tooth l2EL on the striker headv tolimit the rotational movementof thetrigger under the torsional action'of the springand thus hold it in operative positionduring re- Yaccordingly restored to operative position so that on the succeedingdownward stroke it will strike the sear to disengage itfromthe iii-ingpin. It is to be noted that in providing clearance Vfor the sear in thismanner the movement.- ot thetrigger headl isfin the approximatedirection ottravel of the sear and consequently requires but a vminimumdisplacement of the striker head.

Unliket-hosetypesot trigger motors which employ a slide carried by 'the'bolt, there is no Aelement in the present mechanism which willimpede orincrease the load on the sear spring or be liable when disarranged toautomatically trip the sear on return of the bolt int-o battery. Shouldthe springrl in the present device 4be broken anc; the trigger remain inthe lowered position, the Ygun will not run awayl as `the trigger willbeV rotatedv by the sear to inoperative positionwhere itv `will remain.Moreover, the'simplicity of arrangement and the ease of operationrmakefor accuracy and dependability. y

The connection as shown between theY gun and theinotor isillustrativeonly as it isY apparent. that by"reason ot the VaccessibleVmounting vof the trigger in the top plate oi the receiver the connectionis capable :ot innumerablevariations.

lhile inthe foregoing there trated and described such combination andarrangement Vof elements as constitute lthe' preferred.:.embodiment ofthe invention, it is nevertheless desired to `emphasize the fact 'thatinterpreta-tion of the invention should ot the subjoined claims.

- 1. I n Aa machine gun'unit, a receiver, a reciprocal breech bolttherein, a Ytiring Apin only be conclusive when madefin the light hasbeen illus-f carried thereby and movable withv respect thereto,.mcans`tor co'ckinggthe pin, a -verti .cally movable sear ior holding the pinin cocked position, a casing securedto the top plate ot' v,the receiverand depending therein, atrigger rod mounted verticallyin the casing, a'striker head on the lower end ot' said.ti.iggei, acspring for normallyvholding Vthe trigger inp'raised or inoperative posi- -;tion, saidspringalso-adaptedto rotate the trigger and' maintain' the striker headin armedposition, means for intermittently depressing the trigger,andrmeans for limiting both'ieciprocal and rotational movement of thetritfggeii j 2. InV a machine gunfunit.` a reciprocal breech bolt, afiring pin carried thereby and movable with respect thereto, means'liorcocking` the pin, a vertically movable sear for holding the pin incocked positioma trigger rod adapted vto be Vmounted vertically abovethe;sear,.a striker head on the 'lower end of said trigger, a spring fornormally holding thetrigger in raised or inoperative position, saidspring also adapted to yrotate the trigger to maintain the striker headin armed position, and means for limitingrotational movement ot thetrigger.

3. In a machine gun' unit, a-- reciprocal breechbolt, a. tiring pin'carried ytlierebyand movable with respect thereto, means for cockingthepin, a vertically movable Vsear for holding the pin in cockedposition, atrigger rod adapted to lbe mounted vertically above the scar, aV strikerhead on the lower end ot' said trigger capable of rotational movenient,means tor reciprocating the trigger,

and one ot said reciprocal means adapted to restore the striker. head toarm-ed position when'the same has been displaced by the sear. r

' 4. Inf a machine gun unit, a reciprocal -breech bolt, a Vfiringpincarried thereby and ;movable with respect thereto, means torcocking thepin, a verticallyv movable sear for holding the pin in cocked position,a trigger rod adapted to be mounted vertically above the sear, a`striker head Jon the lower'end of said trigger capable of rotationalmovement,

means for reciprocating ,the trigger, `and means for restoring thestriker head to armed position when the same has been displaced by thelsear. y

5. In machine g-un unit, a' reciprocal breech bolt, a firing pin`carried thereby and vmovable with respect thereto, means for cockingthe pin, a sear for holding the pin in cockedpositioina iectilinearlymovable trigger rod for engaging the sear, means for reciprocating therod, and a striker head o'n thelrod movable in the direction ot travelot the sear in providing clearance `for said sear.

6. In a machine gun unit, a reciprocal Vbreech bolt, a firing pincarried thereby and movable with respectvthereto, means vfor cocking thepin, a sear for holding the" pin in cocked position, a rectilinearlymovabletrigger rod for engaging the scar, means for reciprocating therod, and a striker head on the rod movable a minimuml distance inproviding clearance for said sear. I

7. In a machine gun unit, a reciprocal breech bolt, a' firing pincarried thereby and movable With respect thereto, means for cocking theVpin, a sear for holding the pin in cocked position, a rectilinearlymovable trigger rod for releasing the. sre'ar, means for ie- Vcipi'ocatingthe rod, and said .rod adapted to be axially rotated by thesear in providing clearance therefor.

8.v In a Vmachine gun unit, a! reciprocal' breech bolt7 a firing pincarried therebyand movable. with respect thereto, means for cock-A ingthe pin, a sear for holding the pin in cocked position, la rectilinearlymovable trigger rod for. engaging the sear, means foi' reciprocating therod, and said rod adapted to be moved by the sear to unarmed position.

9. In a Vmachine gun unit, a reciprocal breech bolt, a tiring pincarried Vthereby and movable With respect thereto, means for cocking thepin, a sear for holding the pin inv cocked position, a rectilinear-lymovable searengaging trigger rod, and means .tor reciprocating the rod.Y

l0. In ainachine gun unit, areceiver, a' reciprocal breech bolt therein,a iiring pin carried vthereby and movable With respect thereto, meansfor cooking the pin, a seai for holdingthe pinyin cocked position, and avertically reciprocal trigger mounted in the top plate of the receiver.i

l1. In a machinegun unit, alreceivenra thereto, means for cocking thepin, a searitory holding the pin in cocked position, a support extendingWithin the receiver and searact-uf ating means mounted in said support.

13.'In a machine-gun unit, a receiver,"aV Y i reciprocable breech bolttherein, a firing pinir carried 'thereby andvmovable With .respectthereto, means Vfor cooking the pin, afsear for holding the pin injcocked position, a" vertie` f cally disposed support in the top plateofthe lreceiver andI extendingV on 'both' sides thereof and a scaractuatingV means mounted `-invsaijd supporti l 14. Ina machine gununit,a ii'iiig mecn-V anism, a sear therefor,V a rectilinearly'mov.-

able sea-ractuator andnieans adapted to 'be f operated froma distancefor directly actuatiing said sear actuator.

15. In armachine gunl unit, a ringrmechi anism, a scar therefor, ajonekpiece searv actuvstruck by the sear, and means adapted to be; operatedfrom adistancefor directly Voperatingsaid sear actuator.

16. In a machineg'un unit, a reciprocating scar, a i-ectilinearlymovable Sear actuator di rectly engaging the Sear, al cam memberengageable With .said actuator and' ainotor driven vshaft for rotatingthecam member.

17.In a machine'gun unit, a sliding 'scar 'and1 a rectilinearly movableimpulse receiving memberdirectly engageable v'With the sear.

18. In a machine gun unit, a receiver, a

.reciprocabl'e breech bolt therein, a firing pin carriedthereby and-movableWith respect'` thereto, means for coc-king the pin, a scar forholding the pin in vcocked position and a sear rel-ease member mountedfor rectilinear movement andextending through the top plate ofthereeeiver. Y Y Y 19. The combination vWith, a iring'mechanismincludingasear, and a'source'ofsvm chronouspower associated therewith,of a 20;v The combination with a" breechbolt in-V cluding a Sear, of asear tripping element ro.-

tatable about its longitudinal aXisv'When inl 'singleisear trip-pingelement interposed ,be- Y tvveenthe scar and source of power. i .d f

sear trippingposition by thesear When in closing position.

normal position, as the bolt returns to breech l Y `:.sinaUEile. GREEN,i 'f ator mounted for yielding movementvvhen ,70

